From: Thomas Gleixner <[email protected]>

commit 1cf180c94e9166cda083ff65333883ab3648e852 upstream.

free_irq_cfg() is not freeing the cpumask_vars in irq_cfg. Fixing this
triggers a use after free caused by the fact that copying struct
irq_cfg is done with memcpy, which copies the pointer not the cpumask.

Fix both places.

Signed-off-by: Thomas Gleixner <[email protected]>
Cc: Yinghai Lu <[email protected]>
LKML-Reference: <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Signed-off-by: H. Peter Anvin <[email protected]>
Signed-off-by: Paul Gortmaker <[email protected]>
---
 arch/x86/kernel/apic/io_apic.c |   11 ++++++++---
 1 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index abb136a..469d45a 100644
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -303,14 +303,19 @@ void arch_init_copy_chip_data(struct irq_desc *old_desc,
 
        old_cfg = old_desc->chip_data;
 
-       memcpy(cfg, old_cfg, sizeof(struct irq_cfg));
+       cfg->vector = old_cfg->vector;
+       cfg->move_in_progress = old_cfg->move_in_progress;
+       cpumask_copy(cfg->domain, old_cfg->domain);
+       cpumask_copy(cfg->old_domain, old_cfg->old_domain);
 
        init_copy_irq_2_pin(old_cfg, cfg, node);
 }
 
-static void free_irq_cfg(struct irq_cfg *old_cfg)
+static void free_irq_cfg(struct irq_cfg *cfg)
 {
-       kfree(old_cfg);
+       free_cpumask_var(cfg->domain);
+       free_cpumask_var(cfg->old_domain);
+       kfree(cfg);
 }
 
 void arch_free_chip_data(struct irq_desc *old_desc, struct irq_desc *desc)
-- 
1.7.3.3

_______________________________________________
stable mailing list
[email protected]
http://linux.kernel.org/mailman/listinfo/stable

Reply via email to